The present invention relates to a lubricated bearing assembly for the shaft of a yarn spinning rotor.
In German publication, DE-GM No. 69 38 370, a bearing assembly is shown in which the shaft carrying the rotor is held in two spaced grease-lubricated roller bearings within a housing which is provided with an opening for lubrication. A tubular sleeve for guiding a lubricant such as grease, surrounds the shaft between the roller bearings. Lubricant is supplied radially into the sleeve, which then feeds the lubricant through its frontal ends which face the roller bearings. The guide sleeve, which abuts flush on the inner wall of the housing, contains several continuous longitudinal grooves cut into its outer circumferential surface, so as to serve to hold a supply of grease, and at the same time to guide the grease to its two frontal ends. Attached to the frontal ends of the sleeve are metallic rings which are provided with openings aligned with the longitudinal grooves, the cross section of which are smaller than that of the longitudinal grooves. The metallic rings abut on the bearing races of the roller bearings and are heated during the rotation of the bearings by the heat generated in the bearings. As a result of this warming, the grease supply, located at both ends of the longitudinal grooves, melt and discharge from the openings in the rings onto the two roller bearings.
A quantity of grease contained in the central area of the longitudinal grooves, however, does not heat up or heats only to a very slight degree, and this central portion is not utilized for lubrication. Eventually, however, but in an aged condition, this central block of residual grease will be forced to the frontal ends of the longitudinal grooves by refilling the sleeve with additional lubricating grease. To this end, the housing is generally furnished with a nipple which leads into the central portion of the longitudinal grooves so that on introduction of new grease, displacement of the residue in the grooves is caused. The terminal areas of the longitudinal grooves will then contain a mixture of the aged lubricating grease, along with the solid substances of the grease still left there in the form of molten residue. When subsequently warmed during operation, this mixture will yield only a qualitatively poorer lubrication of the bearings.
The present invention has as an object the task of providing a lubrication system for a rotor bearing assembly, which rotor spins with a very high number of revolutions (80,000) and which system will guarantee optimal use of the lubricant supply which requires little maintenance.
A further object is to provide a system which does not result in reduced quality of the lubricant supply for the two roller bearings even during successive refilling of the lubricant reserve as might become necessary after an extended run. These and other objects as well as the advantages of the present invention will be apparent from the following disclosure.